This type of pixel signal processing apparatus is used as part of a color imaging apparatus that also includes an imaging device having multiple types of photoelectric conversion elements, each generating the value of one of a plurality of color components, such as the three primary colors red (R), green (G), and blue (B), arranged in, for example, a Bayer array on a two-dimensional plane, to interpolate color component values that are lacking (missing color component values) at each pixel position according to the pixel signals output from the imaging device.
In conventional imaging apparatus having imaging devices with a Bayer array of red, green, and blue color filters, in which each pixel lacks the green and blue, blue and red, or red and green color component values, interpolation is performed to increase the sense of resolution by replacing the pixel signal of each pixel with a mean value based on the local distribution of pixel signals for each color, thereby employing an interpolation method based on an assumed linear similarity between the known color geometry and the missing color geometry, as shown, for example, in Patent Document 1 below.
Patent Document 1: Japanese Patent Application Publication No. 2001-197512 (paragraphs 0048 to 0049, FIG. 7)